Get a random unique element from an Array until all elements have been picked in Swift

Question

I have the following array:

var notebookCovers = [\"cover1\", \"cover2\", \"cover3\", \"cover4\", \"cover4\", \"cover6\", \"cover7\", \"cover8\", \"cover9\"         


        

Answer 1

If you want to create a looping solution:

let originalSet = Set(arrayLiteral: "a","b","c")
var selectableSet = originalSet

func repeatingRandomObject() -> String {
    if selectableSet.isEmpty {
        selectableSet = originalSet
    }

    return selectableSet.remove(selectableSet.randomElement()!)!
}

force unwrapping is kind of safe here, since we know that the result will never be nil. If you don't want to force unwrap:

let originalSet = Set(arrayLiteral: "a","b","c")
var selectableSet = originalSet

func repeatingRandomObject() -> String? {
    if selectableSet.isEmpty {
        selectableSet = originalSet
    }

    guard let randomElement = selectableSet.randomElement() else { return nil }
    return selectableSet.remove(randomElement)
}